Lubricant



k Patented Jan. 25, 1044 UNITED STATES PATENT 4 OFFICE km: N. white. Chicago. 111.. and Frederick u.

, Munster,!nd.,assig'norsto8tandard Oil Germany,- (lhicago, 111., a corporation of No Drawing- Application June 30, 1941,

Serial No. 400

6 Claims. (or. 196-151) The present invention relates to lubricants having a high viscosity index, a low pour point and a high viscosity.

The lubrication of certain engines, machines and mechanical devices requires lubricants having special properties among which may be listed high viscosity. high viscosity index and low pour point. Lubricants having these special properties are particularly useful in lubricating gears of various kinds such as rear axles, transmissions and the like. Refined mineral lubricating oils will usually fulfill one or two or the above-mentioned requirements but seldom all three. It has been found, in fact, that a mineral oil having a high viscosity index usually does not have a low pour point.

- wax-free and asphalt-free product having a Bay- It is therefore an obiect of the present invention to provide a lubricant which will have both a high viscosity index and a low pour point.

A further object of the present invention is to provide a mineral lubricating oil having a component which will greatly imprdve the viscosityindex,- lower the pour point and at the same time greatly increase the viscosity of the lubricant.

According to thepresent invention the lubricating composition contains a petroleum oil and a high molecular weight hydrocarbon oil. The latter component, because of its high molecular weight, appearance and physical characteristics is sometimes referred to as a "resin'? or a resinous oil," even though its chemical characteristics are far different from those materials, more commonly and more properly known as resins. In order to distinguish the high molecular weight oil more clearly from the comparatively light petroleum oil inthe following description, the former will be referred to hereinafter as a resin-like oil.

While light petroleum oils of differing characteristics may be used, depending on the nature and properties desired in the final product. it has been found that'from about 80% to about 99% of an oil having a viscosity of from about 50 seconds Saybolt Universal at 100' F. to about 1500 seconds Saybolt Universal at 100 F. and a viscosity index of less than l0is suitable. The resin-like oil has a molecular weight of from 1000 to about 2000 and-may be added to the oil in quantities ranging from about-1% to about 40% but preferably from about 10% to about This resin-like oil may be obtained preferably from a Pennsylvania cylinder stock which has been dewaxed at about F. The dewaxed stock is then treated with 4 to 1 0 volumes of propour point.

bolt Universal viscosity at 210 F. of from about 1000 toabout .4000 or more seconds, a viscosiw index of about or more and a relatively high A resin-like oil having suitable characteristics, similar to the foregoingmay be obtained from a mixed base oil such as Mid-Continent crude oil. Obviously, in-this case, it would be necessary to deasphalt as well as dewax the oil before precipitation of the resin-like oil. When a Mid-Continent oil is used the asphalt may be removed by treatment with propane at temperatures of from F. to F., the oil-propane ratio being about1to2.

A more detailed description of the process for obtaining the resin-like oil will be found in U. S. Patents 2,143,872 and aniaaaz.

It is, of course, very often desirable to improve the extreme pressure properties of the lubricant as well as minimize the corrosive eifect of the oil on-various metals. To obtain these additional properties various extreme pressure agents and various corrosion inhibitors may be added to the oil in suitable amounts. Chlorine-containing and sulfur-containing extreme pressure agents may be added, such as for example, chlorinated wax, chloralkyl phosphites, salts of chlorinated al-' .kylated aromatic acids, sulfurized sperm oil. sul- .treme pressure agent and corrosion inhibitor, if

desired, should be selected; according to the type of service to which the lubricant is to be but.

methacrylic polymers and esters may be added if pane at a temperature from about 160 1'. to about 180' P. to produce two phases, a lighter propanesoluble phase and a heavy propane-insoluble phase the resin-like oils. The heavy fnctlonisthmtreatedwithadditionalpropane at Iran r. m rm 2., usually about n,

the ratio 0! llrupanetoheavyoilbeingfrom about Also, various well-lmown viscosity index improv ers such as high molecular weight olefin polymers, 7

desired, although the resin-like oil is usually sufficient for most purposes. The improved lubricant comprising a light petroleum oil and the resin-like oil may be used with or without extreme pressure additives in-the compounding of greases. In Table I the characteristics of compositions containing various proportions of the resin-lib oilandminerallubricatingoilareslven Q Lead naphthenate (corrosion inhibitor)-..

Table I We claim: q 1. A lubricant containing chiefly a mineral lu- Commmou Viscosit Viscosit Viscosity Ponr bricating Oil having a relatively low viscosity index and a viscosity of from about 50 to about 1 1500 seconds Saybolt Universal at 100 F. and from about 1% to about 40% of a resin-like oil obtained by treating a substantially asphalt-free, 1,211 91.5 11.3 wax-free, lubricating oil stock to effect a separa- 1,742 n tion of a light fraction and a heavy traction con- 1 taining the resin-like oil and precipitating the 1,142 90. 9 as. 1 15 resin-like oil from said heavy fraction by treating I said heavy fraction with at least 5 volumes of a I 1,184 91.1 84.0 -15 liquefied normally gaseous hydrocarbon to precipitate a resin-like oil having a viscosity of from 15 about 1000 to about 4000 seconds Sapbolt Uniln Table II the characteristics of 011 No. 1 and oil No. 2 as well as the characteristics of the resinlike oil are given:

Table II vma Viscosit Visoos'it Pour Cmwm 100 at 210 111111111 point n No. 1 oil a 44. o as. a o No.2oil 229 4.1.1 43.3 -s Resin-like oil 2, 910 l 95 +00 dalculated.

' By comparing Tables 1 and n it will be noted that the pour point of the oil Nos. 1 and 2 are Per cent No. 1 on 50.5 No. 2 oil 17 Resin-like oil r. 29

Chlorinated parailln wax (extreme pressure agent) Lead naphthenate (corrosion inhibitor) The characteristics of the above lubricant are given in the following Table III:

resin-like oil obtained by treating a substantially Table III Flash "Pu 390 Pour FL- -10 Moisture Tra'ce Saybolt Universal viscosity at 100' F..... 1,180 Saybolt Universalviscosity at 2" F.. 91.3 Viscosityindex 85.6 Non-combustible sediment per cent 0.012 Cu. strip (24 hrs-at 200 F.)

No stain or discoloration Stability (100 hrs. at 200 F.) test: vis.

increase per cent 2.2

Another example of a lubricant which exhibits, the desired advantages consists of Chlorinated parafiln'wax (extreme pressure agent) a 3.0

High molecular weight olefin polymers (viscosity index improver) 1.5

Although thepresent invention has been described with reference to specific examples, these asphalt-free, wax-free lubricating oil stock with a liquefied normally gaseous hydrocarbon to eilect a phase separation of a light fraction soluble in said liquefied hydrocarbon and a heavy fraction containing the resin-like oil insoluble in said liquefied hydrocarbon, and precipitating the resin-like oil from said heavy fraction by treating said heavy fraction with at least 5 volumes of a liquefied normally gaseous hydrocarbon to precipitate a resin-like oil having a viscosity of from about 1000 to about 4000 seconds Saybolt Universal at 210 F.

3. A lubricant having a high viscosity index and low pour point containing chiefly a mineral lubricating oil. having a viscosity index of less than and from about 10% to about 30% of a resin-like oil obtained by treating a substantially asphalt-free, wax-free lubricating 011 stock with a liquefied normally gaseous hydrocarbon to eil'ect a phase separation of a light fraction soluble in said liquefied hydrocarbon and a heavy fraction containing the resin-like oil insoluble in said liquefied hydrocarbon, and precipitating the resin-like oil from saidheavy fraction by treating said heavy fraction with at least 5 volumes of the liquefied normally gaseous hydrocarbon to precipitate a resin-like oil having a viscosity from about 1000 to about 4000 seconds Saybolt Universal at 210 F.

4. A lubricant having a high viscosity index and a low pour point containing from about 60%. to about 99% of a mineral lubricating oil having a viscosity index below '10 and a viscosity of from about 50 to about 1500 seconds Saybolt Universal at 100 F. and from about 1% to about 40% of a resin-like oil obtainedby treating a substantially asphalt-tree, wax-free lubricating oil stock phase separation of a light fraction soluble in said fied hydrocarbon, and precipitating the resin-like liquefied hydrocarbon and a heavy fraction containing the resin-like oil insoluble in said liqueoil from said heavy fraction by treating said heavy fraction with from about 5 to about 10 volumes of said liquefied normally gaseous hydrocarbon.

5. A method for improving the viscosity index and lowering the pour point of a mineral oil comprising incorporating therewith a minor amount oi a resin-like oil obtained by treating a substantially asphalt-free, wax-free lubricating oil stock to eifect a phase separation of alight fraction and a heavy fraction containing the resinlike oil, and precipitating the resin-like oil from said heavy fraction by treating said heavy fraction with at least 5 volumes of a liquefied normally gaseous hydrocarbon to precipitate a resinlike oil havinga viscosity from about 1000 to about 4000 seconds Saybolt Universal at 210 F.

6. A lubricant 'as claimed in claim 1 wherein' 

